Effects of carbon, nitrogen, and phosphorus stoichiometry on the priming of soil carbon mineralization

Priming effects of soil organic carbon (SOC) decomposition refer to the phenomenon of drastic short-term changes in soil organic matter turnover caused by the addition of exogenous organic materials. Priming effects are key processes that affect carbon dynamics in soil ecosystems. Although the mechanisms responsible for the occurrence and maintenance of priming effects are well understood, most previous studies have only considered the impact of the input of exogenous available organic carbon on priming effects. Carbon, nitrogen, and phosphorus are basic nutrients in soil ecosystems and their stoichiometric ratios regulate the direction and intensity of priming effects by affecting the balance of nutrient availability to microorganisms. In this paper, the research progress on the regulation of the stoichiometric ratio of carbon, nitrogen, and phosphorus on soil priming effects is summarized, and the responses of microbial community structure and activity relevant to soil carbon turnover to different carbon, nitrogen, and phosphorus input ratios are analyzed. Additionally, three mechanisms on the regulation of carbon, nitrogen, and phosphorus stoichiometric ratio on priming effects are summarized, i.e., “co-metabolism” “microbial nutrition mining”, and “stoichiometric decomposition”. It is urgent to apply the theory on the regulation of stoichiometry ratio on soil priming effects for carbon sequestration and emission mitigation in farmland, which benefits China’s “carbon peak and carbon neutrality” dual carbon strategy.